import java.util.*;

class Node {
    int val;
    Node next;
    Node random;

    public Node(int val) {
        this.val = val;
        this.next = null;
        this.random = null;
    }
}
public class Text {

    public static void main(String[] args) {
        String str = "hell";
        str = str.toUpperCase();
        System.out.println(str);
    }

    public static void main1(String[] args) {
        HashBuck hash = new HashBuck();
        hash.put(1, 87);
        hash.put(2, 35);
        hash.put(3, 35);
        hash.put(4, 5);
        hash.put(13, 6);
        hash.put(6, 7);


    }

    public int numJewelsInStones(String jewels, String stones) {
        Set<Character> set = new HashSet<>();
        for (int i = 0; i < jewels.length(); i++) {
            char ch = jewels.charAt(i);
            set.add(ch);
        }
        int count = 0;
        for (int i = 0; i < stones.length(); i++) {
            char ch = stones.charAt(i);
            if (set.contains(ch)) {
                count++;
            }
        }
        return count;
    }

    public static void main4(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNext()) { // 注意 while 处理多个 case
            String a = in.nextLine();
            String b = in.nextLine();
            a = a.toUpperCase();
            b = b.toUpperCase();
            func(a, b);
        }
    }

    public static void func(String str1, String str2) {
        Set<Character> set1 = new HashSet<>();
        for (int i = 0; i < str2.length(); i++) {
            char ch = str2.charAt(i);
            set1.add(ch);
        }

        Set<Character> set2 = new HashSet<>();
        for (int i = 0; i < str1.length(); i++) {
            char ch = str1.charAt(i);
            if (!set1.contains(ch) && !set2.contains(ch)) {
                set2.add(ch);
                System.out.print(ch);
            }
        }
    }

    public int singleNumber(int[] nums) {
        Set<Integer> set = new HashSet<>();
        for (int i = 0; i < nums.length; i++) {
            int val = nums[i];
            if (set.contains(val)) {
                set.remove(val);
            } else {
                set.add(val);
            }
        }

        for (int i = 0; i < nums.length; i++) {
            if (set.contains(nums[i])) {
                return nums[i];
            }
        }
        return -1;

    }

    public Node copyRandomList(Node head) {
        Map<Node, Node> map = new HashMap<>();
        Node cur = head;
        while (cur != null) {
            Node node = new Node(cur.val);
            map.put(cur, node);
            cur = cur.next;
        }

        cur = head;
        while (cur != null) {
            map.get(cur).next = map.get(cur.next);
            map.get(cur).random = map.get(cur.random);
            cur = cur.next;
        }

        return map.get(head);
    }

//    public List<String> topKFrequent(String[] words, int k) {
//        Map<String, Integer> map = new HashMap<>();
//        for(String word : words){
//            if(!map.containsKey(word)){
//                map.put(word, 1);
//            }else{
//                map.put(word, map.get(word) + 1);
//            }
//        }
////        Map.Entry<String, Integer> entry = map.entrySet();
////        PriorityQueue<String> q = new PriorityQueue<>();
////        for(int i = 0; i < k; i++){
////            q.offer()
////        }
//    }

    public boolean containsDuplicate(int[] nums) {
        Set<Integer> set = new HashSet<>();
        for (int i = 0; i < nums.length; i++) {
            if(!set.contains(nums[i])){
                set.add(nums[i]);
            }else{
                return true;
            }
        }
        return false;
    }

    public boolean containsNearbyDuplicate(int[] nums, int k) {
        Map<Integer,Integer> map = new HashMap<>();
        for (int i = 0; i < nums.length; i++) {
            int num = nums[i];
            if(!map.containsKey(num)){
                map.put(num,i);
            }else{
                if(Math.abs(map.get(num)-i) <= k){
                    return true;
                }else{
                    map.put(num,i);
                }
            }
        }
        return false;
    }


}

